This patch set adds support for precise event sampling with IBS. Italso contains IBS fixes and updates not directly related to preciseevent sampling, but found during testing. There are no changes of perftools required, thus this set only contains kernel patches. There willbe also updated perf tools patches available that basically base on myprevious postings to this list and additionally implement IBS pseudoevents.

With IBS there are two counting modes available to count either cyclesor micro-ops. If the corresponding performance counter events (hwevents) are setup with the precise flag set, the request is redirectedto the ibs pmu:

Each IBS sample contains a linear address that points to theinstruction that was causing the sample to trigger. With ibs we haveskid 0.

Though the skid is 0, we map IBS sampling to following precise levels:

1: RIP taken from IBS sample or (if invalid) from stack. 2: RIP always taken from IBS sample, samples with an invalid rip are dropped. Thus samples of an event containing two precise modifiers (e.g. r076:pp) only contain (precise) addresses detected with IBS.

Precise level 3 is reserved for other purposes in the future.

The patches base on a trivial merge of tip/perf/core intotip/perf/x86-ibs. The merge and also the patches are available here:

The following changes since commit 820b3e44dc22ac8072cd5ecf82d62193392fcca3: